This invention relates to an apparatus for working and observing cross sections of samples by irradiating the samples with an ion beam, and a method of working and observing cross sections.
A method of observing cross sections has heretofore been carried out by forming a cross section in the sample by etching the sample by the irradiation with an ion beam. For example, a method has been proposed for forming a cross section by using a focused ion beam lens barrel and by irradiating a focused ion beam on a predetermined position for forming the cross section without using a mask (e.g., see Japanese Patent No. 3117836). According to this method, the cross section that is formed is irradiated with a focused ion beam at a low acceleration voltage and with a small current, or a scanning electron microscope is also used or is separately constituted to irradiate an electron beam, and the cross section is observed by detecting the generated secondary electrons. There has further been proposed a method of effecting the finish working again by the irradiation with a focused ion beam by using a mask after a predetermined position is etched by the irradiation with the focused ion beam (see, for example, JP-A-5-28950).
According to the methods of Japanese Patent No. 3117836 and JP-A-5-28950 which execute the working by using the focused ion beam, the working precision can be improved but limitation is imposed on the amount of electric current for irradiation. Therefore, when a large cross section of a side of about 100 μm is to be worked such as of electronic parts, the working time of about several tens of hours is required. In this case, it can be contrived to work the cross section by a mechanical method without, however, able to maintain precision of position on the cross section. When the cross section is to be observed, further, a device for observation must be separately provided.
The present invention was accomplished in view of the above circumstances, and provides an apparatus for working and observing samples capable of efficiently working and observing even large cross sections of electronic parts maintaining positional precision of cross sections, and a method of working and observing cross sections.